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The objective of this project was to document the early stages of growth of carbonate minerals in the presence of two different organic compounds commonly associated with cell walls or found in biofilms. Organic molecules are believed to influence an environment to be more favorable for carbonate mineral precipitation or serve as a substrate for the initiation of crystal growth. Palmitic and stearic acids are common fatty acids that bind to cell walls and are the most common organic molecules in marine environments. Scanning electron microscope (SEM), transmission electron microscope (TEM), and energy dispersive X-ray spectroscopy (X-EDS) analyses were used to image the interface between the organic molecules and calcite minerals. The SEM and TEM images were used to further understand the interactions between organic compounds and calcite minerals. The palmitic and stearic acid showed a curious formation of spheroidal structures in a spatial relationship with calcite crystal growth. This research is significant because it shows that a spatial relationship exists between organic matter and the mineral calcite. More importantly, the organic material may be acting as a nucleation surface. These experiments represent patterns similar to those observed in nature.

This study is focused on mineralogical and chemical characterization of an authigenic carbonate rock (crust) collected at a recently discovered cold seep on the US North Atlantic continental margin. X-ray diffraction (XRD) and scanning electron microscopy (SEM) indicate that the carbonate rock is composed of microcrystalline aragonite cement, white acicular aragonite crystals (AcAr), equant quartz crystals, small microcrystalline aluminosilicates, and trace amounts of iron sulfide microcrystals. Element/calcium ratios were measured with laser ablation inductively-coupled plasma mass spectrometry (LA-ICP-MS) using a calcite standard, which was prepared by annealing USGS certified carbonate powder (MACS-3). The occurrence of microscopic, non-carbonate inclusions precluded evaluation of trace elements in the aragonite cement, but allowed for in situ analysis of AcAr crystals. Carbon and oxygen isotopes were analyzed via isotope ratio mass spectrometry (IRMS) and expressed as δ13C and δ18O. Low δ13C values suggest that aragonite grew as a result of anaerobic oxidation of methane and observed δ18O values indicate that the temperature of aragonite crystallization was 1.7–1.9 °C.

The objective of this study is to better understand the relationship between organic compounds and carbonate mineral growth in different natural environments by imaging the interface between organic compounds and carbonate precipitates in ancient and modern rocks, and laboratory experiments. Three separate projects were designed to document the organic/carbonate mineral interface through imagery. 1) Images of the interfaces between organic components and initial mineral precipitates were investigated in a deteriorating microbial mat from Vermelha, Brazil that was taken from the site in 2006. As the mat deteriorated the amount of calcification increased. A section of the transitional section between living algae and calcitic precipitate was taken for analysis. Transmission Electron Microscopy (TEM) along with Energy-dispersive X-ray spectroscopy (X-EDS) showed carbonate minerals growing on cell walls and using dark, amorphous structures as nucleation points. X-EDS results showed that the dark amorphous structures have high concentrations of silica, magnesium, and oxygen, which appears to promote carbonate mineral precipitation. 2) Laboratory experiments were designed to precipitate calcite in solution with varying organic compounds and then use TEM analysis to image the precipitants, specifically the transitional area between the organic compounds and carbonate minerals. Calcite crystals appeared to nucleate off of the surfaces of palmitic and stearic acid. X-EDS analysis verified the elemental transition from organic matter to carbonate mineral growth. 3) Cold water, authigenic carbonate rocks collected by Dr. Adam Skarke, on July 6, 2016 during the National Oceanographic Laboratory System (UNOLS) research cruise to a methane seep off the eastern North America coast were imaged and analyzed. Scanning Electron Microscope (SEM), EDS and XRD analysis were used to better understand the sequence of events that led to formation of this unusual rock. The rock grew in situ trapping quartz and metallic minerals in aragonitic cement, and then was cut and pushed apart by veins filled with aragonitic cement in a pattern reminiscent of septarian nodules.

This study is focused on mineralogical and chemical characterization of an authigenic carbonate rock (crust) collected at a recently discovered cold seep on the US North Atlantic continental margin. X-ray diffraction (XRD) and scanning electron microscopy (SEM) indicate that the carbonate rock is composed of microcrystalline aragonite cement, white acicular aragonite crystals (AcAr), equant quartz crystals, small microcrystalline aluminosilicates, and trace amounts of iron sulfide microcrystals. Element/calcium ratios were measured with laser ablation inductively-coupled plasma mass spectrometry (LA-ICP-MS) using a calcite standard, which was prepared by annealing USGS certified carbonate powder (MACS-3). The occurrence of microscopic, non-carbonate inclusions precluded evaluation of trace elements in the aragonite cement, but allowed for in situ analysis of AcAr crystals. Carbon and oxygen isotopes were analyzed via isotope ratio mass spectrometry (IRMS) and expressed as δ 13C and δ 18O. Low δ 13C values suggest that aragonite grew as a result of anaerobic oxidation of methane and observed δ 18O values indicate that the temperature of aragonite crystallization was 1.7–1.9 ◦C.

The objective of this project was to test the hypothesis that micritic, microbial, dendritic shrub structures transition into aragonite botryoids by serving as an organic substrate that promotes the initiation of aragonite crystal precipitation. Samples for this study were taken from three sources: 1) a stalactite found in the Lighthouse Reef Blue Hole, Belize; 2) aragonite botryoids in the reef framework of the Permian Capitan Formation and 3) the Lower Permian Laborcita Formation found in the Sacramento Mountains, south-central New Mexico. Samples studied in thin section and with scanning electron microscopy (SEM) showed dendritic micrite within botryoids and spheroidal shapes associated with aragonite. Precipitation experiments were conducted to grow calcite crystals with organic molecules in solution. The textures formed were very similar to those found at the three sample sites. Despite the similarity, all evidence of an organic substrate promoting precipitation remains circumstantial and therefore inconclusive.

Polycam is a mobile app that generates 3D models of objects using high-resolution Photogrammetry or LiDAR (Light Detection and Ranging) technology. LIDAR scanning is available on Apple devices labeled Pro, such as the iPhone 12 Pro and iPad Pro. This project explores the accuracy of Photogrammetry scans in comparison to НРАВ scans. Testing took place on a geologic outcrop in Fort Smith, Arkansas. Scans using both methods were conducted at 1-meter intervals, extending up to a total distance of five meters from the outcrop. The internal measuring system in Polycam was utilized to assess the geologic and lighting obstacles at each scan point. The measurements obtained from Polycam were then compared to physical measurements to evaluate accuracy across different scanning distances. LiDAR camera scans were conducted with an iPad Pro, 12.9- inch (5th generation). An iPhone 12 was used for the optical camera Photogrammetry scans. Field testing showed LiDAR equipped devices captured more accurate images. The accuracy for Polycam using a LIDAR camera was within 2.5-centimeter resolution in well-lit areas, comparable to more expensive standalone LiDAR units.

SIGNAL is a multicenter, randomized, double-blind, placebo-controlled phase 2 study (no. NCT02481674) established to evaluate pepinemab, a semaphorin 4D (SEMA4D)-blocking antibody, for treatment of Huntington’s disease (HD). The trial enrolled a total of 265 HD gene expansion carriers with either early manifest (EM, n  = 179) or late prodromal (LP, n  = 86) HD, randomized (1:1) to receive 18 monthly infusions of pepinemab ( n  = 91 EM, 41 LP) or placebo ( n  = 88 EM, 45 LP). Pepinemab was generally well tolerated, with a relatively low frequency of serious treatment-emergent adverse events of 5% with pepinemab compared to 9% with placebo, including both EM and LP participants. Coprimary efficacy outcome measures consisted of assessments within the EM cohort of (1) a two-item HD cognitive assessment family comprising one-touch stockings of Cambridge (OTS) and paced tapping (PTAP) and (2) clinical global impression of change (CGIC). The differences between pepinemab and placebo in mean change (95% confidence interval) from baseline at month 17 for OTS were −1.98 (−4.00, 0.05) (one-sided P  = 0.028), and for PTAP 1.43 (−0.37, 3.23) (one-sided P  = 0.06). Similarly, because a significant treatment effect was not observed for CGIC, the coprimary endpoint, the study did not meet its prespecified primary outcomes. Nevertheless, a number of other positive outcomes and post hoc subgroup analyses—including additional cognitive measures and volumetric magnetic resonance imaging and fluorodeoxyglucose–positron-emission tomography imaging assessments—provide rationale and direction for the design of a phase 3 study and encourage the continued development of pepinemab in patients diagnosed with EM HD. The SIGNAL Phase 2 study of pepinemab immunotherapy in early Huntington’s disease (HD) did not meet its coprimary clinical efficacy endpoints, but had a favorable safety profile and showed a significant treatment-related reduction in caudate brain atrophy and reversal of the characteristic decline in brain metabolic activity that is typical of HD progression.

Hyperpolypharmacy (≥ 10 daily medications) is frequent in patients with chronic kidney disease (CKD), but its impact remains poorly characterized. This study, based on 3,011 non-dialyzed, non-transplant CKD outpatients from the CKD-REIN cohort (eGFR < 60 mL/min/1.73 m 2 ) aimed to describe drug burden and assess associations between hyperpolypharmacy and adverse outcomes. Drug prescription, kidney function, adverse drug reactions (ADRs), hospitalizations, kidney replacement therapy and deaths before KRT were prospectively recorded over five years. Median age was 69 years and mean eGFR was 34 mL/min/1.73 m 2 . At baseline, 80% of the cohort had polypharmacy (≥ 5 daily medications), and 33% had hyperpolypharmacy. These rates remained stable over time. Diabetes, dyslipidemia, and a history of cardiovascular and respiratory diseases were the main contributors to hyperpolypharmacy status. Hyperpolypharmacy was associated with greater likelihoods of an ADR (hazard ratio (HR) [95% confidence interval (CI)] 1.21 [1.04–1.40]), hospitalization (HR [95%CI] 1.34 [1.18–1.51]) and death before KRT (HR [95%CI] 1.46 [1.17–1.82]). Among patients with eGFR ≥ 30 mL/min/1.73m 2 , hyperpolypharmacy also raised the risk of KRT initiation (HR [95%CI] 1.46 [1.00–2.13]), but not in those with eGFR < 30 (HR [95%CI] 0.94 [0.78–1.14]). These results identify hyperpolypharmacy as a significant concern in CKD and underscore the importance of regular medication reviews to reduce adverse outcomes.

Low-mass pre-main sequence (PMS) stars are strong and variable X-ray emitters, as has been well established by EINSTEIN and ROSAT observatories. It was originally believed that this emission was of thermal nature and primarily originated from coronal activity (magnetically confined loops, in analogy with Solar activity) on contracting young stars. Broadband spectral analysis showed that the emission was not isothermal and that elemental abundances were non-Solar. The resolving power of the Chandra and XMM X-ray gratings spectrometers have provided the first, tantalizing details concerning the physical conditions such as temperatures, densities, and abundances that characterize the X-ray emitting regions of young star. These existing high resolution spectrometers, however, simply do not have the effective area to measure diagnostic lines for a large number of PMS stars over required to answer global questions such as: how does magnetic activity in PMS stars differ from that of main sequence stars, how do they evolve, what determines the population structure and activity in stellar clusters, and how does the activity influence the evolution of protostellar disks. Highly resolved (R>3000) X-ray spectroscopy at orders of magnitude greater efficiency than currently available will provide major advances in answering these questions. This requires the ability to resolve the key diagnostic emission lines with a precision of better than 100 km/s.